bstring.c
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// RUN: %clang_analyze_cc1 -verify %s \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=unix.cstring \
// RUN: -analyzer-checker=alpha.unix.cstring \
// RUN: -analyzer-checker=debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false
//
// RUN: %clang_analyze_cc1 -verify %s -DUSE_BUILTINS \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=unix.cstring \
// RUN: -analyzer-checker=alpha.unix.cstring \
// RUN: -analyzer-checker=debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false
//
// RUN: %clang_analyze_cc1 -verify %s -DVARIANT \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=unix.cstring \
// RUN: -analyzer-checker=alpha.unix.cstring \
// RUN: -analyzer-checker=debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false
//
// RUN: %clang_analyze_cc1 -verify %s -DUSE_BUILTINS -DVARIANT \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=unix.cstring \
// RUN: -analyzer-checker=alpha.unix.cstring \
// RUN: -analyzer-checker=debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false
//===----------------------------------------------------------------------===
// Declarations
//===----------------------------------------------------------------------===
// Some functions are so similar to each other that they follow the same code
// path, such as memcpy and __memcpy_chk, or memcmp and bcmp. If VARIANT is
// defined, make sure to use the variants instead to make sure they are still
// checked by the analyzer.
// Some functions are implemented as builtins. These should be #defined as
// BUILTIN(f), which will prepend "__builtin_" if USE_BUILTINS is defined.
// Functions that have variants and are also available as builtins should be
// declared carefully! See memcpy() for an example.
#ifdef USE_BUILTINS
# define BUILTIN(f) __builtin_ ## f
#else /* USE_BUILTINS */
# define BUILTIN(f) f
#endif /* USE_BUILTINS */
typedef typeof(sizeof(int)) size_t;
void clang_analyzer_eval(int);
//===----------------------------------------------------------------------===
// memcpy()
//===----------------------------------------------------------------------===
#ifdef VARIANT
#define __memcpy_chk BUILTIN(__memcpy_chk)
void *__memcpy_chk(void *restrict s1, const void *restrict s2, size_t n,
size_t destlen);
#define memcpy(a,b,c) __memcpy_chk(a,b,c,(size_t)-1)
#else /* VARIANT */
#define memcpy BUILTIN(memcpy)
void *memcpy(void *restrict s1, const void *restrict s2, size_t n);
#endif /* VARIANT */
void memcpy0 () {
char src[] = {1, 2, 3, 4};
char dst[4] = {0};
memcpy(dst, src, 4); // no-warning
clang_analyzer_eval(memcpy(dst, src, 4) == dst); // expected-warning{{TRUE}}
// If we actually model the copy, we can make this known.
// The important thing for now is that the old value has been invalidated.
clang_analyzer_eval(dst[0] != 0); // expected-warning{{UNKNOWN}}
}
void memcpy1 () {
char src[] = {1, 2, 3, 4};
char dst[10];
memcpy(dst, src, 5); // expected-warning{{Memory copy function accesses out-of-bound array element}}
}
void memcpy2 () {
char src[] = {1, 2, 3, 4};
char dst[1];
memcpy(dst, src, 4); // expected-warning {{Memory copy function overflows the destination buffer}}
#ifndef VARIANT
// expected-warning@-2 {{memcpy' will always overflow; destination buffer has size 1, but size argument is 4}}
#endif
}
void memcpy3 () {
char src[] = {1, 2, 3, 4};
char dst[3];
memcpy(dst+1, src+2, 2); // no-warning
}
void memcpy4 () {
char src[] = {1, 2, 3, 4};
char dst[10];
memcpy(dst+2, src+2, 3); // expected-warning{{Memory copy function accesses out-of-bound array element}}
}
void memcpy5() {
char src[] = {1, 2, 3, 4};
char dst[3];
memcpy(dst + 2, src + 2, 2); // expected-warning{{Memory copy function overflows the destination buffer}}
#ifndef VARIANT
// expected-warning@-2{{memcpy' will always overflow; destination buffer has size 1, but size argument is 2}}
#endif
}
void memcpy6() {
int a[4] = {0};
memcpy(a, a, 8); // expected-warning{{overlapping}}
}
void memcpy7() {
int a[4] = {0};
memcpy(a+2, a+1, 8); // expected-warning{{overlapping}}
}
void memcpy8() {
int a[4] = {0};
memcpy(a+1, a+2, 8); // expected-warning{{overlapping}}
}
void memcpy9() {
int a[4] = {0};
memcpy(a+2, a+1, 4); // no-warning
memcpy(a+1, a+2, 4); // no-warning
}
void memcpy10() {
char a[4] = {0};
memcpy(0, a, 4); // expected-warning{{Null pointer passed as 1st argument to memory copy function}}
}
void memcpy11() {
char a[4] = {0};
memcpy(a, 0, 4); // expected-warning{{Null pointer passed as 2nd argument to memory copy function}}
}
void memcpy12() {
char a[4] = {0};
memcpy(0, a, 0); // no-warning
}
void memcpy13() {
char a[4] = {0};
memcpy(a, 0, 0); // no-warning
}
void memcpy_unknown_size (size_t n) {
char a[4], b[4] = {1};
clang_analyzer_eval(memcpy(a, b, n) == a); // expected-warning{{TRUE}}
}
void memcpy_unknown_size_warn (size_t n) {
char a[4];
void *result = memcpy(a, 0, n); // expected-warning{{Null pointer passed as 2nd argument to memory copy function}}
clang_analyzer_eval(result == a); // no-warning (above is fatal)
}
//===----------------------------------------------------------------------===
// mempcpy()
//===----------------------------------------------------------------------===
#ifdef VARIANT
#define __mempcpy_chk BUILTIN(__mempcpy_chk)
void *__mempcpy_chk(void *restrict s1, const void *restrict s2, size_t n,
size_t destlen);
#define mempcpy(a,b,c) __mempcpy_chk(a,b,c,(size_t)-1)
#else /* VARIANT */
#define mempcpy BUILTIN(mempcpy)
void *mempcpy(void *restrict s1, const void *restrict s2, size_t n);
#endif /* VARIANT */
void mempcpy0 () {
char src[] = {1, 2, 3, 4};
char dst[5] = {0};
mempcpy(dst, src, 4); // no-warning
clang_analyzer_eval(mempcpy(dst, src, 4) == &dst[4]); // expected-warning{{TRUE}}
// If we actually model the copy, we can make this known.
// The important thing for now is that the old value has been invalidated.
clang_analyzer_eval(dst[0] != 0); // expected-warning{{UNKNOWN}}
}
void mempcpy1 () {
char src[] = {1, 2, 3, 4};
char dst[10];
mempcpy(dst, src, 5); // expected-warning{{Memory copy function accesses out-of-bound array element}}
}
void mempcpy2 () {
char src[] = {1, 2, 3, 4};
char dst[1];
mempcpy(dst, src, 4); // expected-warning{{Memory copy function overflows the destination buffer}}
#ifndef VARIANT
// expected-warning@-2{{'mempcpy' will always overflow; destination buffer has size 1, but size argument is 4}}
#endif
}
void mempcpy3 () {
char src[] = {1, 2, 3, 4};
char dst[3];
mempcpy(dst+1, src+2, 2); // no-warning
}
void mempcpy4 () {
char src[] = {1, 2, 3, 4};
char dst[10];
mempcpy(dst+2, src+2, 3); // expected-warning{{Memory copy function accesses out-of-bound array element}}
}
void mempcpy5() {
char src[] = {1, 2, 3, 4};
char dst[3];
mempcpy(dst + 2, src + 2, 2); // expected-warning{{Memory copy function overflows the destination buffer}}
#ifndef VARIANT
// expected-warning@-2{{'mempcpy' will always overflow; destination buffer has size 1, but size argument is 2}}
#endif
}
void mempcpy6() {
int a[4] = {0};
mempcpy(a, a, 8); // expected-warning{{overlapping}}
}
void mempcpy7() {
int a[4] = {0};
mempcpy(a+2, a+1, 8); // expected-warning{{overlapping}}
}
void mempcpy8() {
int a[4] = {0};
mempcpy(a+1, a+2, 8); // expected-warning{{overlapping}}
}
void mempcpy9() {
int a[4] = {0};
mempcpy(a+2, a+1, 4); // no-warning
mempcpy(a+1, a+2, 4); // no-warning
}
void mempcpy10() {
char a[4] = {0};
mempcpy(0, a, 4); // expected-warning{{Null pointer passed as 1st argument to memory copy function}}
}
void mempcpy11() {
char a[4] = {0};
mempcpy(a, 0, 4); // expected-warning{{Null pointer passed as 2nd argument to memory copy function}}
}
void mempcpy12() {
char a[4] = {0};
mempcpy(0, a, 0); // no-warning
}
void mempcpy13() {
char a[4] = {0};
mempcpy(a, 0, 0); // no-warning
}
void mempcpy14() {
int src[] = {1, 2, 3, 4};
int dst[5] = {0};
int *p;
p = mempcpy(dst, src, 4 * sizeof(int));
clang_analyzer_eval(p == &dst[4]); // expected-warning{{TRUE}}
}
struct st {
int i;
int j;
};
void mempcpy15() {
struct st s1 = {0};
struct st s2;
struct st *p1;
struct st *p2;
p1 = (&s2) + 1;
p2 = mempcpy(&s2, &s1, sizeof(struct st));
clang_analyzer_eval(p1 == p2); // expected-warning{{TRUE}}
}
void mempcpy16() {
struct st s1[10] = {{0}};
struct st s2[10];
struct st *p1;
struct st *p2;
p1 = (&s2[0]) + 5;
p2 = mempcpy(&s2[0], &s1[0], 5 * sizeof(struct st));
clang_analyzer_eval(p1 == p2); // expected-warning{{TRUE}}
}
void mempcpy_unknown_size_warn (size_t n) {
char a[4];
void *result = mempcpy(a, 0, n); // expected-warning{{Null pointer passed as 2nd argument to memory copy function}}
clang_analyzer_eval(result == a); // no-warning (above is fatal)
}
void mempcpy_unknownable_size (char *src, float n) {
char a[4];
// This used to crash because we don't model floats.
mempcpy(a, src, (size_t)n);
}
//===----------------------------------------------------------------------===
// memmove()
//===----------------------------------------------------------------------===
#ifdef VARIANT
#define __memmove_chk BUILTIN(__memmove_chk)
void *__memmove_chk(void *s1, const void *s2, size_t n, size_t destlen);
#define memmove(a,b,c) __memmove_chk(a,b,c,(size_t)-1)
#else /* VARIANT */
#define memmove BUILTIN(memmove)
void *memmove(void *s1, const void *s2, size_t n);
#endif /* VARIANT */
void memmove0 () {
char src[] = {1, 2, 3, 4};
char dst[4] = {0};
memmove(dst, src, 4); // no-warning
clang_analyzer_eval(memmove(dst, src, 4) == dst); // expected-warning{{TRUE}}
// If we actually model the copy, we can make this known.
// The important thing for now is that the old value has been invalidated.
clang_analyzer_eval(dst[0] != 0); // expected-warning{{UNKNOWN}}
}
void memmove1 () {
char src[] = {1, 2, 3, 4};
char dst[10];
memmove(dst, src, 5); // expected-warning{{out-of-bound}}
}
void memmove2 () {
char src[] = {1, 2, 3, 4};
char dst[1];
memmove(dst, src, 4); // expected-warning{{Memory copy function overflows the destination buffer}}
#ifndef VARIANT
// expected-warning@-2{{memmove' will always overflow; destination buffer has size 1, but size argument is 4}}
#endif
}
//===----------------------------------------------------------------------===
// memcmp()
//===----------------------------------------------------------------------===
#ifdef VARIANT
#define bcmp BUILTIN(bcmp)
int bcmp(const void *s1, const void *s2, size_t n);
#define memcmp bcmp
//
#else /* VARIANT */
#define memcmp BUILTIN(memcmp)
int memcmp(const void *s1, const void *s2, size_t n);
#endif /* VARIANT */
void memcmp0 () {
char a[] = {1, 2, 3, 4};
char b[4] = { 0 };
memcmp(a, b, 4); // no-warning
}
void memcmp1 () {
char a[] = {1, 2, 3, 4};
char b[10] = { 0 };
memcmp(a, b, 5); // expected-warning{{out-of-bound}}
}
void memcmp2 () {
char a[] = {1, 2, 3, 4};
char b[1] = { 0 };
memcmp(a, b, 4); // expected-warning{{out-of-bound}}
}
void memcmp3 () {
char a[] = {1, 2, 3, 4};
clang_analyzer_eval(memcmp(a, a, 4) == 0); // expected-warning{{TRUE}}
}
void memcmp4 (char *input) {
char a[] = {1, 2, 3, 4};
clang_analyzer_eval(memcmp(a, input, 4) == 0); // expected-warning{{UNKNOWN}}
}
void memcmp5 (char *input) {
char a[] = {1, 2, 3, 4};
clang_analyzer_eval(memcmp(a, 0, 0) == 0); // expected-warning{{TRUE}}
clang_analyzer_eval(memcmp(0, a, 0) == 0); // expected-warning{{TRUE}}
clang_analyzer_eval(memcmp(a, input, 0) == 0); // expected-warning{{TRUE}}
}
void memcmp6 (char *a, char *b, size_t n) {
int result = memcmp(a, b, n);
if (result != 0)
clang_analyzer_eval(n != 0); // expected-warning{{TRUE}}
// else
// analyzer_assert_unknown(n == 0);
// We can't do the above comparison because n has already been constrained.
// On one path n == 0, on the other n != 0.
}
int memcmp7 (char *a, size_t x, size_t y, size_t n) {
// We used to crash when either of the arguments was unknown.
return memcmp(a, &a[x*y], n) +
memcmp(&a[x*y], a, n);
}
int memcmp8(char *a, size_t n) {
char *b = 0;
// Do not warn about the first argument!
return memcmp(a, b, n); // expected-warning{{Null pointer passed as 2nd argument to memory comparison function}}
}
//===----------------------------------------------------------------------===
// bcopy()
//===----------------------------------------------------------------------===
#define bcopy BUILTIN(bcopy)
// __builtin_bcopy is not defined with const in Builtins.def.
void bcopy(/*const*/ void *s1, void *s2, size_t n);
void bcopy0 () {
char src[] = {1, 2, 3, 4};
char dst[4] = {0};
bcopy(src, dst, 4); // no-warning
// If we actually model the copy, we can make this known.
// The important thing for now is that the old value has been invalidated.
clang_analyzer_eval(dst[0] != 0); // expected-warning{{UNKNOWN}}
}
void bcopy1 () {
char src[] = {1, 2, 3, 4};
char dst[10];
bcopy(src, dst, 5); // expected-warning{{out-of-bound}}
}
void bcopy2 () {
char src[] = {1, 2, 3, 4};
char dst[1];
bcopy(src, dst, 4); // expected-warning{{overflow}}
}
void *malloc(size_t);
void free(void *);
char radar_11125445_memcopythenlogfirstbyte(const char *input, size_t length) {
char *bytes = malloc(sizeof(char) * (length + 1));
memcpy(bytes, input, length);
char x = bytes[0]; // no warning
free(bytes);
return x;
}
struct S {
char f;
};
void nocrash_on_locint_offset(void *addr, void* from, struct S s) {
size_t iAdd = (size_t) addr;
memcpy(((void *) &(s.f)), from, iAdd);
}